Choke for oil wells



Feb. 14, 1933.

H. c. o'rls 3,897,985

CHOKE FOR O IL WELLS Filed April 2l, 1930 2 Sheets-Sheet l Feb. 14,1933n H. c. o'rls CHOKE FOR OIL WELLS Filed April 2l, 1950 2Sheets-Sheet 2 OO `f OO OO HJ. MTL y y Mw o #u d 'I Patented Feb. 14,1933 UNITED s'ra'rlazs HERBERT C. OTIS, F SHBEVEPORT, LOUISIANA CHOKEFOB OIL WELLS Application led April 21,

This invention relates to chokes for oil wells.

One of the objects of this invention is to provide a choke tube for oilwells which has means whereby the device will be secured in positionwithin the well .when it is lowered.

Another object of this invention is to provide a choke tube which may beeasily and conveniently removed from vthe well.

Another object of this invention is to protiide a choke tube havingself-adjusting packing means. u

Another object of this invention is to provide suitable apparatus forplacing and removing such a choke or like device.

Further objects will appear from the detail description taken inconnection with the' accompanying drawings in which Fig. 1 is anelevation showing the device with the lowering mechanism.

Fig. 2 is a view partly in section showing the device in position in awell and engage by lifting tongs. l

Fig. 3 is a vertical cross-section, Fig. 1.

Fig. 4 is a vertical cross-section, Fig. 2.

Fig. 5 is a sectional Viewr of lowering tongs on line 5 5, Fig. 3. y

A cylindrical choke tube 1 has at its upper end a circumferential iange2, and has at its' lower end exterior threads 3. f

A sleeve mandrel 4 is positioned about'and in sliding engagement withthe tube 1 and is reamed to provide'a shoulder 5 adapted to engage theiange 2 on the tube. I The outer circumferential surface has a taper 6,and at its upper end a .circumferential groove 7 which forms the topflange 8. The outer surface of the mandrel is bevelled as shown at 9.

A plurality of slips 10, having teeth 11, are resiliently attached tothe tube 1 by leaf springs 12, which may be secured to the tubes in anyconvenient manner as by the screws 13.

.The taper 6 of the mandrel 4 is such that downward movement of themandrel from its initial position in which the shoulder 5 o'f themandrel is in engagement with the flange 2 of the tube, will force0 theslips 10 outward against the casing, causing the engagement 1930. SerialNo. 445,963.

of the teeth 11 to prevent upward movement of the tube.

A ,ring 14 is secured to the tube 1, as by welding, and forms an abuttinsurface for a packing sleeve 15 of yielding material, which maypreferably be of rubber. Beneath the packing sleeve 15, a collar 16 ismounted on and in sliding engagement with the tube 1. The collar 16 issecured against downward movement displacement by a nut 17 in engagementwith the threads 3.

v The arrangement of the packing sleeve 15 and the collar 16 is suchthat, when the tube is in position in the well and a fluid pressure visbeing exerted on it from the bottom, the

collar 16 will be forced upwardly compressing the packing material 15and forcin it out against the casing, thus forming a uid seal betweenthe tube and the casing.

The apparatus for lowering and raising the choke includes a cable 18, aset of jars 19 and 20, a pair of tongs 21 for lowerin and a pair oftongs 22 for raising the c oke. The jar elements'19 and 2() are intelescopic engagement as shown in the drawings. The jar elements arehollow and the upper element 19 has perforations 23. rlhe cable 18 maybe secured to a separate detachable ele ment 24 which is fastened by athreaded connection 25 to the upper jarelement 19.

The tongs 21 and 22 are preferably pivot ed to a se arate detachableelement 26, which is secure to the lower jar element 20 by a threadedconnection 27. The legs of the tonos are mounted on pivot pins 28secured in the element 26 by the cotters 29. Each leg of the tongs 21has an oblique section 30 and a vertical section 31 carrying an engagingjaw 32 having a bevelled surface 33. Co operating stops 34 are placed oneach of the legs to llmit their inward movement, and a spring 35 holdsthe tongs in a fixed position.

The tongs 22 are similar to tongs 21 except thatlonger vertical sections36 are pro-- vided on, the legs. Otherwise, in the drawings, thereference characters used in connection with the tongs 21 are used toidenti the respective parts of the tongs 22. The' vertical section 36 isof such a length as to accommodate the full travel of the mandrel 4 withrespect to the tube 1, the function of which will be more apparent fromthe following description of the manipulatlon, and operation of theapparatus and choke.

If it is desired to set the choke at the base of the casing, a shoulderon which to set the tube must be provided. In such a case a perforatedanchor of the desired length is connected to the lower .end of the tubeby the threads 3. lIf, however, it is desired to set the tube at anintermediate point in the hole, no anchor or distance Jpiece isnecessary. The tongs 21 are attached to the mandrel and the assembly islowered into the well by the steel cable 18. The steel cable is runthrough a stuffing box at the casing head and all the flow through thetubing is cut oli' during the operation. Displaced fluid passes botharound the entire assembly and up through the orice in the tube l,through the center orifice in the jars 19, 20, and through theperforations 23. If the assembly is lowered until its lower end restsupon a liner in the well or until the perforated anchor reaches thebottom of the well or tubing, the continued travel of the weighted jars19, 20, will press the mandrel 4 downward, forcing the slips 10 outwardand against the casing.

This movement may be assisted by spudding e with the jars 19 and 20.

When the mandrel 4 has traveled downward with respect to the tube 1 asullicient distance as to force the slips 10 in engagement with thecasing, the top of the tube l will come into engagement with the obliquesections 30 of the tongs 21 and force their opening, releasing themandrel. The lowering mechanism may then beremoved from the hole andflow permitted from the well by opening the surface gate valves. Thedifferential set up at the base of the tube assembly orces the collar 16upward, extending the packing sleeve 15 against the casing, and extendsthe slips 10 still more tightly against the casing.

If it is desired to set the choke at a point some distance from thebottom, the assembly is lowered to'that point and flow from thewellslowly started. The liuid movement will tend to raise the tube withits integral elements upward while the jars hold the mandrel in a fixedposition, thus causing the slips 10 to engage the casing wall andrelease the tongs. If the teeth on the slips are sharp no further uppermovement of the tube will occur. The movement of the fluid moves thecollar 16 upward compressing the packing sleeve 15. If the well isallowed to low for a few hours the slips will become tightly engagedwith the casing and the packing sleeve will be tightly wedged betweenthe tube and the casing so that the choke will not move downward if theflow is stopped.

lVhen it is desired to remove the choke from the hole the jar assemblyis equipped with the ton s 22 having the longer vertical legs 36 and t eassembly is. lowered into the well.` The bevelled surface 33 on thetongs engage with the bevelled ring 9 on the mandrel and the aws 32 thengrasp the to ilange 8 of the mandrel. AA pull on the ca le-will raisethe mandrel bringing its shoulder 5 into engagement with the top flange2 of the tube, releasing the slips 10 causing them to move toward thetube-and away from the casing. The assembly is then in condition to beraised from the well. The packing sleeve 15 will not wedge the tubesuliciently tight to pre-A vent removal, especiall since an upward pullwill elongate the pac lng sleeve by reason of the sliding connection ofthe-lower collar 16 with. the tube.

It will thus be seen that a choke tube has been provided which has meansreadily operable to hold it in position after it is lowered into thewell, in connection with means for packing between the tube and thecasing so as to make the choke eiective. The choke has been providedwith means which, taken in connection with novel apparatus alsoprovided, enables the choke to be readily placed in and removed from awell.

This application is related to my application Serial No. 558,208, filedAugust 20, 1931, in which application I have claimed the methoddisclosed herein.

It is obvious that various changes may be made in the details ofconstruction within the scope of the appended claims, without departingfrom the spirit of this invention; and that various parts may be usedseparately without the whole.

I claim:

1. A choke for oil wells comprising, a tube smaller in exterior diameterthan the well casing, a plurality of slips arranged circumferentiallyabout the tube, a tapered mandrel in sliding engagement with the tubeand tapered to force the slips outwardly against the casing, means onthe mandrel for engaging tongs and means actuated by downward travel ofthe mandrel for releasing the ton s.

2l A choke for oil wells comprising, a tu e smaller in, exteriordiameter than the well casing, a plurality of slips arrangedcircumerentially 'about the tube, a tapered mandrel in slidingengagementy with the tube adapted to force -the slips outwardly againstthe casing, and means on the mandrel for engaging tongs; the tubes,mandrel and tongs being arranged and adapted so that ull downwardmovement of the mandrel causes the top of the tube to engage the legs ofV ment with the tube adapted by downward movement to force the slipsoutward, in combination with a pair of lowering tongs having means toengage the mandrel and means cooperating with the tube'to release thetongs when the mandrel has been moved to a securing position.

4. A choke for oils wells comprising, a tube smaller in exteriordiameter than the well casing, a plurality of slips adapted by outwardmovement to engage the well casing, a tapered mandrel about and insliding engagement with the tube adapted by upward movement to releasethe slips, in combination with a pair of tongs having means to engagethe mandrel for placement of the choke.

5. A choke for oil wells comprising a cylinder smaller in exteriordiameter than the well bore, a plurality of slips arranged about thecylinder, a mandrel between the cylinder and slips arranged whendepressed to spread the slips, and means on the mandrel for engagingtongs whereby theI4 choke may be lowered to position.

6. A choke for oil wells comprising a cylinder smaller in exteriordiameter than the,

well bore, a plurality of slips arranged about the'cylinder, a mandrelbetween the cylinder and slips arranged when depressed to spread theslips, means on the mandrel for engaging tongs whereby the choke may be.

lowered to position, and an abutment on the cylinder adapted to engagethe mandrel and prevent its displacement. v

7. A choke for oil wells comprising a cylinder smaller in exteriordiameter than the wellV bore, aV plurality of slips arranged about thecylinder, a mandrel between the cylinder and slips arrangedwhendepressed to spread the slips in combination with weighted tongsadapted to engage the mandrel, and jars from which the tongs aresuspended and adapted to force the mandrel in downward position. ,y l

8. A device for insertion in a well including a vertical shaft on` thedevice, slips for engaging a well casing disposed about said shaft andresiliently attached thereto, and a tapered mandrel mounted between saidshaft and said slips waereby a downward movement of the mandrel on theshaft will spread the slips to engage the well casing, in combinationwith lowerin tongs adapted to engage the mandrel, sai lowering tongshaving oblique leg sections arranged and 'ada te to engage the top ofthe shaft to sprea the legs of the tongs and release the device when themandrel has been lowered to spread the sli s.

g. A device for insertion in awell including a vertical shaft on thedevice, slips for engaging a well casing disposed about said shaft andresiliently attached thereto, and a tapered mandrel mounted between saidshaft and said,V slips whereby a downward movement of the mandrel on theshaft will spread shaft.

.. HERBERT C. OTIS.

